There is a growing practice to package many articles in plastic film enclosures rather than in paperboard cartons or the like. For example, many canned and bottled food and beverage products are now being packaged by placing them on simple linerboard or plastic trays and then passing them through conventional heat shrink apparatus in which they are wrapped in a shrinkable film material, usually polyethylene, which is then heat shrunk in place. This package technique is used in cases in which it has been conventional practice in the past to use corrugated cartons. These individual packages, which may consist of twelve or twenty-four cans or bottles of a product, are then loaded on pallets for shipment.
Because they slide relatively easily with respect to one another, they must be anchored to the pallet by suitable means. It is common to use shrink wrap palletizing techniques, wherein the pallet and load are enclosed at least in part by a sheet or preformed sleeve of heat-shrinkable film and then passed through a shrink tunnel where heat is applied and the film tightly shrunk about the load. A most commonly used heat shrink material for this purpose is polyethylene film; however, when such film is shrunk on loads of individual packages where the packages themselves are wrapped in polyethylene film, the shrinking heat applied in the tunnel causes the outer polyethylene sheet or sleeve to fuse to the individual packages on the pallet, thus making it difficult if not impossible to remove the individual packages intact from the pallet when they reach their destination.
The problem is similar in smaller six and eight-pack packages of containers which are wrapped in shrink wrap film or film and foam laminates. It is becoming common practice to wrap an assembled group of bottles in a heat-shrinkable preformed sleeve, and then wrapping a number of such packages into a larger integral package or unit.